Reading Diagnostic Trouble Codes

Diagnostic Mode 03 - Read DTC Memory

Diagnostic Mode 03 makes it possible to read emissions-related faults (confirmed DTCs: faults which have activated the MIL) in the ECM and in the TCM.

When the Engine Control Module (ECM) recognizes an emission related fault it turns on the Malfunction Indicator Lamp (MIL) or if a Electronic Throttle Malfunction is recognized, the Engine Control Module (ECM) turns on the Electronic Power Control (EPC) Warning Lamp which are both located in the instrument cluster.

The DTCs are sorted by SAE code with the DTC tables consisting of a 5-digit alpha-numeric value.

NOTE: Depending on scan tool and protocol used, diagnostic mode 03 and the information provided may be referred to by a different name.

The following tables provide a breakdown and explanation of the DTC code.

P-Codes










U-Codes







Procedure
- Connect the scan tool.
- Switch the ignition to the "ON" position.
- Select "Diagnostic Mode 03: Interrogating fault memory ".
- The stored DTC or DTCs will be displayed on the scan tool screen.

The following table is an example of the DTC information that may be displayed on the scan tool screen:

Indication example Explanation
P0444 SAE Diagnostic Trouble
Code (DTC)
Evaporative Emission (EVAP) Malfunctioning wiring path or
Canister Purge Regulator Valve malfunctioning component
Circuit Open Malfunction type as next

- Refer to the DTC tables for the diagnostic repair procedure:
- SAE P0xxx DTCs. P000A
- SAE P1xxx DTCs. P1009
- SAE P2xxx DTCs. P2088
- SAE P3xxx DTCs. P3081
- SAE U0xxx DTCs. U0001

- Switch the ignition off.